test(review): add the 4 new test-coverage points from PR #185 re-review

The re-review's blocking/structural points (lease leak, dup-id guard test,
body-before-title test, CHANGELOG, pg18, shared jsonb decoder) were already
addressed in commit 24264ef; this adds the 4 genuinely-new coverage requests:

- pt 6: `scrollToReference(id, index?)` exercised against a live editor DOM —
  selects the index-th `sup[data-footnote-ref][data-id]` occurrence, falls back
  to the first for out-of-range, returns false for an empty id (scrollIntoView
  stubbed). (#168)
- pt 7: export `backlinkLabel` and pin the base-26 carry boundary
  (25->z, 26->aa, 27->ab, 51->az, 52->ba). (#168)
- pt 8: integration fail-open — a PRESENT-but-corrupt tool_allowlist (jsonb
  string scalar holding non-array JSON) reads back as null ("no restriction"),
  covering normalizeRow's degrade branch. (#159 #172/#173)
- pt 9: getFootnoteRefCount cache invalidation — adding a `[^a]` reference bumps
  the cached count 2 -> 3. (#168)

Verified: editor-ext footnote 23; client structure 7 + tsc; server int 8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/client/src/features/editor/components/footnote/footnote-definition-view.tsx

@@ -7,7 +7,7 @@ import classes from "./footnote.module.css";
  * A 0-based backlink index -> its lowercase letter label (0 -> "a", 25 -> "z",
  * 26 -> "aa", ...), matching the Pandoc/Wikipedia "↩ a b c" convention.
  */
-function backlinkLabel(index: number): string {
+export function backlinkLabel(index: number): string {
   let out = "";
   let x = index;
   while (x >= 0) {

apps/client/src/features/editor/components/footnote/footnote-views.structure.test.tsx

@@ -75,7 +75,9 @@ vi.mock("@/features/editor/components/code-block/mermaid-view.tsx", () => ({
 }));
 
 import FootnotesListView from "./footnotes-list-view";
-import FootnoteDefinitionView from "./footnote-definition-view";
+import FootnoteDefinitionView, {
+  backlinkLabel,
+} from "./footnote-definition-view";
 import CodeBlockView from "../code-block/code-block-view";
 
 // Minimal NodeViewProps stub: definition view only touches node.attrs.id and
@@ -214,3 +216,16 @@ describe("#168 footnote definition multi-backlinks", () => {
     );
   });
 });
+
+// #185 re-review pt 7: backlinkLabel is base-26 (a..z, then aa…). The component
+// tests only cover a,b,c (index 0-2); pin the >= 26 carry boundary.
+describe("backlinkLabel base-26 boundary (#168)", () => {
+  it("maps 0->a, 25->z, 26->aa, 27->ab, 51->az, 52->ba", () => {
+    expect(backlinkLabel(0)).toBe("a");
+    expect(backlinkLabel(25)).toBe("z");
+    expect(backlinkLabel(26)).toBe("aa");
+    expect(backlinkLabel(27)).toBe("ab");
+    expect(backlinkLabel(51)).toBe("az");
+    expect(backlinkLabel(52)).toBe("ba");
+  });
+});

apps/server/test/integration/ai-mcp-server-repo.int-spec.ts

@@ -91,6 +91,25 @@ describe('AiMcpServerRepo tool_allowlist jsonb round-trip [integration]', () =>
     const healed = enabled.find((r) => r.id === id);
     expect(healed?.toolAllowlist).toEqual(['alpha', 'beta']);
   });
+
+  it('FAIL-OPEN: a present-but-corrupt tool_allowlist reads back as null (no restriction)', async () => {
+    // #185 re-review pt 8: normalizeRow's fail-open branch — the column is
+    // PRESENT but does not parse into a string[] (here a jsonb string scalar
+    // holding non-array JSON). The read must degrade to `null` ("no restriction"),
+    // not crash. (A warn is logged with the server id; not asserted here.)
+    const id = randomUUID();
+    await sql`
+      INSERT INTO ai_mcp_servers (id, workspace_id, name, transport, url, tool_allowlist)
+      VALUES (
+        ${id}, ${ws}, ${`srv-${id}`}, 'http', 'https://example.com/mcp',
+        to_jsonb(${'{"not":"an array"}'}::text)
+      )
+    `.execute(db);
+    // Sanity: the column is present (a jsonb string scalar), not SQL NULL.
+    expect(await jsonbTypeof(id)).toBe('string');
+    // ...yet the read degrades to null (fail-open).
+    expect((await repo.findById(id, ws))?.toolAllowlist).toBeNull();
+  });
 });
 
 /**